Of course, it's quite possible that you're a fan of multiple inheritance, so you can do that, too (I was soooooo tempted to not allow this, but I figured I shouldn't force too many of my personal beliefs on you):

If called with no arguments, returns the current value. If called with one argument, sets that argument as the current value. If called with more than one argument, it croaks.

ABSTRACT CLASSES

You may pass an optional is_abstract parameter in the import list. It takes a boolean value. This value is advisory only and is not inherited. It defaults to false if not provided.

Sometimes you want to identify a test class as "abstract". It may have a bunch of tests, but those should only run for its subclasses. You can pass <is_abstract = 1>> in the import list. Then, to test if a given class or instance of that class is "abstract":